Eccrine adenocarcinoma. A clinicopathologic study of 35 cases.

A clinicopathologic study was made of 35 patients with primary eccrine adenocarcinoma diagnosed in the past 20 years from among 450,000 consecutive skin biopsy specimens. Histologically the following four distinct variants were identified: eccrine porocarcinoma (18 cases), syringoid eccrine carcinoma (12 cases), mucinous eccrine carcinoma (three cases), and clear cell eccrine carcinoma (two cases). Overall, eccrine adenocarcinomas are destructive lesions with a tendency to local recurrence. The syringoid histologic variant appears to be well differentiated and may have a benign clinical course; the lesion remained localized to the skin in our 12 cases. Regional lymphatic and distant metastasis, however, occurred in two patients with eccrine porocarcinoma.